Kūmara - Kūmara

Kūmara (sweet potato) has a long history of cultivation in New Zealand.

Kūmara was brought here over one thousand years ago from the Pacific islands by early Maori settlers. This bush had much smaller tubers and was widely grown, especially in the semi-tropical regions of the North Island. Pre-European Maori managed kūmara-growing with great skill. They grew several different varieties of 'bush' kūmara, which, compared to the varieties we eat today, were very small in size, being no bigger than a finger.

Modern kūmara grows on a creeping vine and evolved from a larger American variety with bigger tubers and better taste which was imported in the early 1850s. The majority of kūmara is grown in Northland in the Northern Wairoa region where soil type and climatic conditions suit it perfectly.

Varieties

There are different varieties of kūmara, however, only three main varieties are commercially available in New Zealand. The most common is the red-skinned, Owairaka Red, which has a creamy white flesh and is sold as Red; gold kūmara, sometimes sold as Toka Toka Gold, has a golden skin and flesh, and a sweeter taste than red; orange kūmara, sometimes sold as Beauregard, has a rich orange flesh and is sweeter than both red and gold. Beauregard kūmara can be used instead of yams in North American recipes.

What to look for

Look for kūmara that are firm with smooth and unbroken skin. Date stamped product packaging gives a reliable measure of freshness. Buy regularly, no more than a week’s supply.

Availability

Available: all year

Store

Kūmara should be stored in a cool, dark place that is well ventilated. Do not refrigerate.

How to prepare

Peel, wash and portion. However, it is not always necessary to peel kūmaras; if leaving skin on, scrub skin well and remove blemishes.

Ways to eat

Kūmara is a very versatile vegetable; it can be mashed, barbecued, used in soups, stir fries, pies, quiches, braises or stews; cooked as chips or wedges or baked whole; thin kūmara slices will puff up into crisps. To use kūmara in salads, first cook until soft, and then cool. Kūmara goes well with all meats and also complements fruits such as banana, pineapple, apricot and apple.

Cooking methods

Braise, bake, boil, char grill, microwave, roast, steam, stew, stir fry, stuff.

Nutrition

Kūmara is a source of dietary fibre and contains a dietary significant amount of potassium (they are one of the highest potassium-containing vegetables). Kūmara is one of the highest carbohydrate containing vegetables so it makes an excellent source of energy. The coloured flesh and skin of kūmara supply an array of phytonutrients including phenolic compounds, flavonoids and carotenoids. Red or purple varieties contain anthocyanins (found in the skin of red varieties), and those with orange and yellow colouring are rich in beta-carotene. The richer the colour the more phytonutrients present.

Red kūmara is a good source of vitamin C and niacin; a source of dietary fibre, thiamin, vitamin B6, manganese and contains a dietary significant amount of potassium.

Gold kūmara is a good source of folate, riboflavin, vitamin A and vitamin B6; a source of dietary fibre, niacin, thiamin, copper and magnesium, and contains a dietary significant amount of potassium.

Orange kūmara is a good source of vitamin A; a source of dietary fibre, niacin, riboflavin, thiamin, vitamin B6, vitamin C and manganese, and contains a dietary significant amount of potassium.

Nutrition table

Retailing

Buy small quantities regularly and employ good stock rotation principles. Handle kūmara with care, they are not as hardy as they look and they do bruise easily. Rough treatment will shorten storage and shelf life and cause costly wastage. When stacking crates or boxes on top of each other, the weight must be borne by the crates, or boxes, and not the product. Only buy product packed in boxes that are strong enough to withstand the weight.

Store at 13-17°C with a relative humidity of 75-80%. Kūmara should be stored in a cool, dark well ventilated place. Kūmaras should never be refrigerated or stored at less than 12°C as this will result in chilling damage which results in shrivelling, increased decay, surface pitting and sometimes causes a hard core to develop. This hard core will fail to soften during cooking. Sprouting becomes a problem at higher storage temperatures.

Kūmara are ethylene sensitive so store separately from ethylene producing fruits and vegetables. Use the QR code on labels.

Purchase kūmara with the New Zealand GAP logo.